MB QUART RA1-710.5 700 Watt 5-Channel Amplifier Car Stereo Amp+Bass Remote

The RA1-710.5 is a five-channel Class D amplifier that powers a full system from one chassis: four full-range channels for front and rear speakers plus a dedicated subwoofer channel. Output is 4 x 50W plus 150W at 4 ohms, 4 x 100W plus 150W at 2 ohms, and 350W on channel 5 alone at 1 ohm, which is stable enough for most single subwoofer builds. MB Quart splits the topology by job, running Class SQ for the full-range channels and Class Q1 for the subwoofer channel, both Class D, with the Q-Stasis preamplifier stage feeding them clean signal. Signal to noise exceeds 101dB and THD stays under 0.07 percent, with full-range response from 10Hz to 35kHz and 10 to 250Hz on channel 5. Channels 1 and 2 plus channels 3 and 4 each get switched full or high-pass filters from 50Hz to 250Hz, while channel 5 has a variable low-pass over the same range, plus 0 to 12dB bass boost and a switchable 25Hz subsonic filter. Input sensitivity spans 0.02 to 9V, and DC Signal Sense powers the amp from RCA signal so no remote turn-on wire is needed. The wired bass remote ships in the box. FLUID-FETS output devices, an aluminum heat sink, and a rugged MOSFET pulse width modulation power supply keep heat and current draw manageable. The chassis weighs 7.4 lb, takes 4 AWG power wire, and uses an 80A external fuse.